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    <title>Document</title>
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<body>
    <div class="mmm">123</div>
    <div class="aaa">啊啊啊</div>
    <div class="mmm">啊啊啊</div>
    <ul>
        <li>
            <div class="mmm">456</div>
        </li>
    </ul>
    <div class="mmm">dfd</div>

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    <script>
        alert($(".mmm").html())
        $(".mmm").html(function (index, html) {
            console.log(index, "--", html)
        })
        $(".mmm").html("jdfei")
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